Synchronous disease onset and flares in siblings with PFAPA

Background Periodic fever, aphthous stomatitis, pharyngitis, and cervical adenitis (PFAPA) is a clinical syndrome of unclear etiology. PFAPA has generally been considered a non-hereditary fever syndrome; however, this has been called into question with recent reports of family clustering. Few reports have been published describing siblings with PFAPA. To our knowledge, this is the first report of siblings with near simultaneous onset of disease followed by synchronous disease flares. Case Presentation: We describe the case of near simultaneous onset of periodic fever, aphthous stomatitis, pharyngitis, and cervical adenitis in siblings followed by synchronous disease flares of clear frequency and nearly identical character. Flares were characterized predominantly by fever, aphthous ulceration, cervical lymphadenitis, and the absence of infection. The fever episodes demonstrated a robust response to glucocorticoids and recurred in the same staggered manner every four weeks, with complete absence of symptoms and normal growth and development between episodes. Nine months after onset, the older sibling, a 5-year-old female, underwent tonsillectomy resulting in dramatic resolution of episodes. At the same time, her 2-year-old sister experienced resolution of her fever episodes, though she did not undergo tonsillectomy herself. Conclusion This is an unusual case of simultaneous onset PFAPA followed by synchronous disease flares. PFAPA is an uncommon clinical syndrome, and it is rarely diagnosed in siblings. The etiology of PFAPA remains unclear. Though the disease is classically considered sporadic, there is a growing body of evidence to suggest that PFAPA may be heritable.